Work channeling device for shoe sewing machines



Dec. 17, 1940. 0/12. HAAs 2,225,301

WORK CHANNELING DEVICE FOR SHOE SEWING MACHINES Filed May 10, 1939 menial Patented Dec. 17, 1940 UNITED STATES WORK CHANNELING DEVICE FOR SHOE SEWING MACHINES Otto R. Haas, North Beverly, Mass, assignor to United Shoe Machinery Corporation, Borough of Flemington, N. J., a corporation of New Jersey Application May 10, 1939, Serial No. 272,777

11 Claims.

The present invention relates to work channelling devices for outsole shoe sewing machines, and more particularly to that type of channelling device having a grooving knife mounted on the presser foot of a shoe sewing machine.

The objects of the present invention are to provide a channelling device which is simpler and more easily constructed than previous devices of this nature without rendering it less effective or shorter lived in use. Other objects are to provide an improved presser-foot for a shoe sewing machine which may be employed with or without a groove cutting knife while at the same time remaining as effective under either condition as previous devices designed for one purpose only. A still further object is to provide a novel form H of groove cutting knife which may readily be adapted for different types of work without complicated adjustments being made in the machine with which it is employed. Accordingly, one feature of the present invention relates to a work channelling device for a shoe sewing machine including a presser-foot formed with a lug having a circular bore within which a flat sided groove cutting knife is clamped, the presser-foot being provided with a knife engaging surface outside the bore in the lug to prevent rotation of the knife. By this construction, the bore in the lug may be drilled through in the usual way stopping just short of the knife engaging surface on the presser-foot. Thus, when the knife is clamped, it is effectively secured against movement lengthwise in the lug and against rotation without the expense of a breaching operation ordinarily required in a flat sided or non-circular knife receiving bore. In the form of this feature, as illustrated, the knife engaging surface is flat and partly obstructs the end of the bore. Preferably the grooving knife is of triangular cross-section 0 so that cutting edges are formed at both ends by the apex of the angularly disposed sides and one end of the knife is offset from the main body so that when the knife is reversed in the bore of the 45 presser-foot the cutting edge at the offset end will act at a point further from the axis of the bore than the cutting edge at the straight end of the knife. By using the offset end of the knife, the cutting edge may be made to act at a 5 point closer to the stitch-forming devices, which relation is particularly desirable with narrow pointed shoes having fine stitches. For coarser work where a deeper channel is required, the straight end of the knife may be employed to ad- 55 vantage.

The several features of the present invention will be clearly understood from an inspection of the accompanying drawing in which Figure 1 is a view in front elevation of a channel cutting device embodying the features of the present in- 5 vention; Figure 2 is a view in left-hand side elevation of the device illustrated in Figure 1; Figure 3 is a plan view of the device; Figure 4 is a sectional view on an enlarged scale taken along the line 44 of Figure 1; Figure 5 is another sec- 10 tional view on the same scale taken along the line. 5-5 of Figure 1; and Figure 6 is a detail view partly in section on a similar scale of the work engaging portion of the device.

As illustrated in the drawing, the device is an 15 improvement over a previous channel cutting device illustrated in U. S. Letters Patent to Meyer No. 1,048,719 of December 31, 1912, and is intended for use in an outsole shoe sewing machine of the type referred to in that patent. The de- 20 vice is intended to take the place of the regular presser-foot of the machine and is secured to a presser-foot lever l0 indicated in dot-dash lines by means of screws l2 passing through horizontal slots in the lever and into threaded engagement with the device. The presser-foot portion I4 of the device has its lower end shaped with a workengaging face l6, and with sharpened ridges [8 running in the direction of feed to assist in main taining the work in sewing relation with the stitch-forming devices.

To cut a channel for the seam in the work, the presser-foot portion M has formed on it a lug 20 having a circular bore 22, the axis of which is inclined at an acute angle to the work engaging face of the presser-foot for receiving a grooving knife 24 having an equilateral triangle cross section, the bore 22 being of a size to accommodate the knife with. its angular edges supported against the inner circular surface of the bore. When disposed in the bore 22 with its end projecting a short distance beyond the face IS; the knife. 24 drags along the surface of the Work in line with and in advance of the seam.

In order to insure that the knife is held at the proper angle and to prevent rotation of the knife in the circular bore, the presser-foot has a flat surface 26 between the lug 20 and the work engaging face of the presser-foot. The surface 26 50 obstructs oneside of the circular bore 22 and is arranged in the proper relatoin with the bore to support one side of the knife 24 near its lower end. To secure the knife in the bore 22, a set screw 28 is threaded through one. side of the lug and engages the knife along an angular edge between two of its sides to clamp the third side of the knife against the fiat surface 26, the screw 28 being at the opposite side of the axis of the bore from the surface 26. In forming the bore 22, an ordinary twist drill is employed, and after having passed throug h' the'lug 20, the drill is removed without clearing out the obstruction formed by the surface 26. Thus, a simple and effective means is provided for holding the knife 24 securely in place without complicated machining operations.

Cutting edges on kniveshaving uniform triangular cross section are conveniently formed by the apices of the angularly disposed sides and,

to avoid interfering with the stitch-forming devices of a sewing machine, the ends of such knives ordinarily are beveled asat 30. In order to provide means for adjusting the point at which the knife of the present device operates relatively tothe presser-foot portion of thedevice, one end of the knife 24, as illustrated in Figure 1, is offset from the main body of the knife, the offset indicated at 32 being formed by welding a separate piece onto the main body of the knife with corresponding sides of the piece and main bo'dyin parallel relation. When thus arranged; the knife maybe reversed to change the cutting point of the knife with relation to the presser-foo tand stitch-forming devices, either closer to the stitch-forming devices when operating onfine work, or further away on coarser heavier work. ,When fine work is being operated upon, and particularly with shoes having narrow pointed toes, the offset end of the knife being operative, the cut will be formed close to the stitch-forming devices so that a sharp turn in the seam may conveniently bemade. When coarser work is being sewn, the offset endof the knife mayinterfere with the feeding movements of thestitch-forming devices so that 'itis desirable to reverse the knife with the straight end in operative position. Other simple adjustments may-readilybe made with the device, such as movement of the'knife in the lug 20 towards and from an operative position when the screw 28 is loosened andtransversely to the seam line byloosening the holding screws 12 and changing thdhorizontal position of the whole device on the presser-foot lever ill of the machine.

The nature and scope of the invention having been indicated, and a particular embodiment having beendescribed, what is claimed is:

1. A work channelling device for a shoe sewing machine having, in combination, a presserfoot "formed with a work engaging face and a lug having a-circular bore the axis of whichis transverseto the work engaging face of the presserfoot, a flat sided work grooving knife received in the bore projecting beyond the work engaging face of the presserfoot, means for clamping the knife in the bore, and a knife engaging surface on the presser-foot outside the bore in the lug for holding the knife from rotation in the bore; l v

2. Awork channelling devicefor a-shoesewing machine having, in combination, a presserfoot formed with a work engaging face and a lug having a circular bore the axis of which is transverse to thework engagingface of the presserfoot; a fiat sided work grooving knife received in the'bore projecting beyond the work engaging faceof the presser-foot, means for clamping the knifeinthe bore, and a flat knife engaging sur face outside the lug on the presser-foot, partly obstructing one end of the bore in the lug to hold the knife from rotation in the bore when clamped.

3. A work channelling device for a shoe sewing machine, having, in combination, a presserfoot formed with a work engaging face and a lug having a circular bore the axis of which is transverse to the work engaging face of the presser- -foot, a knife engaging surface on the presserfoot partly obstructing one end of the bore in the lug, and a work grooving knife of triangular cross section supported in part by the knife engaging surface. when projecting from the bore beyond the work engaging face of the presser-foot.

' 4. A work channelling device for a shoe sewing machine having, in combination, a presserfoot formed with a work engaging face and a lug havinga circular bore the axis of which is transverse to the work engaging face of the presserfoot, a knife engaging surface on the presserfoot partly obstructing one end of the bore in the lug, and a work grooving knife of triangular cross section supported in part by the knife engaging surface of the presser-foot, said knife having cutting edges at either end with one end offset from the main body of the knife to act on the work beyond the work engaging face of the presser-foot at a point further from the axis of the bore in the lug than the cutting edge at the other end of the knife when the knifeis reversed.

5. A work channelling device for a shoe sewing machine having, in combination, a presserfoot formed with a work engaging face and a lug having a circular bore the axis of which is transverse to the work engaging face, of the presser-foot, a knife engaging surface on the presser-foot partly obstructing one end of the bore in the lug, a work grooving knife of triangular cross section supported by the knife engaging surface of the presser-fooa and a set screw entering the bore in the lug to engage the knife along an angular portion of its outer surface.

6. A presser-foot for a shoe sewing machine comprising a work engaging face, a lug having a circular bore, the axis of which is transverse to the work engaging face for receiving a work grooving knife, and a knife engaging surface on the presser-foot, partly obstructing the bore, in the lug.

7. A presser-foot for a shoe sewing machine comprising a work engaging face, a lughaving a circular bore, the axis of which is transverse to the work engaging face for receiving a work grooving knife, a knife engaging surface on the presser-foot extending outside the bore in the lug and obstructing the end thereof, and knife clamping means entering the bore at the side thereof opposite the knife, engaging surface.

8. A presser-foot for a shoe sewing machine comprising a work engaging face, a lug having a circular bore, the axis of which is transverse to the work engaging face for receiving a work grooving knife, knife clamping means entering the bore at one side thereof, and a knife engaging surface on the presser-foot partly obstructing the bore at the other side thereof and extending outside the bore between the lug and the work engaging face of the presser-foot.

9. A presser-foot fora shoe sewing machine comprising a work engaging face, a lug having a circular bore, the axis. of which is transverse to the work engaging face for receiving a work grooving knife, knife clamping means entering the bore at one side thereof, and a knife engaging surface on the presser-foot obstructing the bore suificiently to support one side of a knife of equilateral triangle section having outside dimensions to fit within the circular bore.

10. A work grooving knife for a shoe sewing machine comprising a bar formed with a cutting edge at either end with one end offset from the 10 main body of the knife acting on the work at a different location than the other end when the knife is reversed.

11. A Work grooving knife for a shoe sewing machine comprising a bar of equilateral triangular section with cutting edges formed at both ends by transverse faces and with one end offset from the main body of the knife and disposed with the side surfaces parallel to the side surfaces of the main body of the knife.

OTTO R. HAAS. 

